Method of producing catalytic cores



Aug. 30, 1932. A. E HARNSBERGER ET AL 1,874,743

METHOD, OF PRODUCING CATALYTIC CORES Original Filed Aug. 21, 1928 4 Qwventoz fl EHarnSberyer 6. Z Sm I'l /L Patented Aug. 30, 1932 UNITED STATES PATENT OFFICE AUDLEY E. EABNSBERGER AND CLYDE L. SMITH, OF C HICA C O', ILLINOIS, ASSIGNORS T GYRO PROCESS COMPANY, OF- DETROIT, MICHIGAN, A CORPORATION OF MICH- IGAN METHOD OF PRODUCING CATALYTIC CORES Original application filed August 21, 1928, Serial No. 801,152. Divided and this application flied December 14,,1929. Serial No. 414,167.

This invention relates to an improved type of catalytic core of the type used in connection with processes and apparatus for cracking petroleum oils. In certain of these processes oil is heated to substantially a state of vapor and is then passed through tubes or pipes for further heat treatment so that the temperature. of the oils or vapors will be raised sufficiently to effect molecular decomposition thereof. It has been found certain systems that by arranglng within the tubes or pipes where the oil is heated to cracking temperatures, the conversion reactions are facilitated through bringing such vapors into contact with reaction promoting mate rials, among which'may be mentioned ferrous oxide, although other materials are and have been used for this purpose. a

It is desirable in such systems ofoil cracking to maintain a uniform flow of oil vapor at constant velocity through the converting elements. For this reason it is undesirable to place the catalytic material in loose or bulk form in the converting elements for the reason that the flow of vapor is rendered ununiform and frequently the tubes or elements are clogged or blocked so that overheating is produced. In the cracking of petroleum oils time and temperature are the important factors, and the time factor must be as carefully controlled" as the temperature factor. For this reason it has been proposed that cores composed of catalytic substances be provided, wherein the cores are composed of, for example, ferrous oxide mixed with a binder such as cement for the purpose of fproducing an elongated core possessing uni orm diameter and of substantially solid formation. Such a core, in operation, possesses a considerably smaller diameter than the inside diameter of the tube or pipe, or other convertingelement in which it is situated, with the result that there remains an annular space in the converting element through which the vapors under heat treatment pass usually at high velocity.

The use of such cores, however, has demonstrated that imder practical operating conditions they are very apt to burst, with the result that the tubeor converting element is formed.

obstructed and it is neecssary to shut down temporarily the operation of the converter until the burst core or filler has been removed and a new one substituted. This is due to the fact that internal pressure is built up therein either by reason of high co-eflicient of expansion, the growth of the ,core or filler under high temperatures, or the building up of high gas pressure inside of the core.

We have found that by making the cores more porous and not a solid mass that the conditions mentioned above are largely over come. One method of accomplishing this is to produce a mixture consisting of substantially ninety parts of iron oxide and cement and ten parts of sawdust, placing this mixture in a perforated pipe in a packed state and then subjecting the perforated pipe and its internal filler to a high temperature so as to drive off the moisture and to carbonize the sawdust. This results in a porous core which permits internal pressure to be readily removed or prevented with the result that the core is less apt to break or burst when subjected to the high temperatures found in the operation of oil conversion systems.

This application is a division of our previous application, Serial Number 301,152, filed August 21, 1928.

For a further understanding of the invention reference is to be had to the following description and the accompanying drawing wherein:

Figure 1 is a view in side elevation of a catalytic core formed in accordance with the present invention,

Figure 2 is a vertical sectional view taken through the core showing the latter positioned with a tubeof the oil converter,

Figure 3 is a view in side elevation and partly in vertical section of a slightly modified form of core,

Figure 4 is a similar view of a further modified type of core,

Figure 5 is a view in side elevation of the perforated container in which the core is L In accordance with the present invention, there is provided a core 1 consisting of an elongated body which is substantially round 'ferrous oxide.

in a cross section and made of any suitable weight, this being a factor which is regulated by the len h of the converter element or pipe 2 in whlch the core is situated when in operation in an oil conversion system. It will be observed that the core possesses an outside diameter which is substantially less wire legs 4. The latter rest upon the bottom of the pipe 2 and serve to centralize and support the core axially within said pipe and at the same time offer the least resistance to the passage of the oil vapors through the space 3.

The core is composed preferably of iron oxide, concrete or other cementitious materials which are mixed with sawdust or the like, that is to say, there isemployed roughly 10 per cent'of sawdust to 90 per cent of iron oxide ,and cement. These materials are placed while wet or moist in container 5 which consists preferably of a tubular or cylindrical metallic body suitably perforated as ,at 6. The core materials are suitably acked in the container and then the latter 1s placed in a furnace and subjected to sufficiently high temperatures to drive off the,

moisture and to carboni'ze the sawdust content thereof. This results in the production of an extremely porous core in which it will be practically impossible for as to pocket or accumulate and which will t erefore prevent the bursting of the cores and the premature destruction thereof when subjected to the operating temperatures and conditions which prevail in the converting element or pipe 2 of the oil conversion system.

The second method for accomplishing similar results is to make the center of the core hollow, as shown in Figure 3. This can be accomplished-by placing in the center of the container 5 a wooden rod or staff indicated at 7, around which is packed the concrete and This core is then subjected to heat for the purpose of carbonizing the rod 7 to produce an axial passage within the core so that any internal pressure can be relieved throu h the center section or passage. The core s own in Figure 3 may also include in the body thereof a certain percent of sawdust so that the walls of the core will be rencore could easily collapse under abnormal pressures or strains.

Through the provision of the above construction it will be seen that by rendering the material porous as disclosed provision is made to compensate for high internal pressures to prevent the fracture of such materials and the perforate steel casing surrounding the same. As previously explained, these perforate steel casings were formerly filled solidly with the concrete and ferrous oxide with the result that when the cores or fillers wereplaced in a converter tube and subjected to the high temperatures there prevading, usually 1100 F., the tremendous stresses set up inside of these perforate pipes or cases would result frequently in the bursting of the same. This difliculty is believed to be due principally to the growth of the material under the temperature causing high internal pressure. However, in accordance with the present invention the filler or core is rendered'porous by the use of the sawdust in the compositions thereof, and the resulting porosity produced by the construction results in relieving the strain since it gives room for ex pansion due to the growth of the material under the influence of heat.

What is claimed is: I a

1-. The method of producing catalytic cores for use in tubular oil heaters, which consists in producing a plastic mixture composed of a material possessing catalytic activity in oil' cracking reactions, an organic substance and a cementitious material, molding said mixture while in said plastic state in the form of an elongated rod or core, and then subjecting said mixture to temperatures sufliciently high to effect the carbonization of said organic material and a hardening or setting of the mixture into a permanent rod-like form, wherebysaid rod or core possesses a 105 consists in producing a plastic mixture com- 110 posed of a material possessing catalytic activ- 1ty in oil cracking reactions, an organic substance and a cementitious material, molding said mixture in the form of an elongated rod or core, then subjecting said mixture to tem- 115 peratures sufliciently high to effect the carbonization of said organic material and a hardening or setting ofthe mixture into a substantially porous permanent rod-like form, and releasing the volatiles from said mixture as rapidly as they are formed during the heating of said materials.

3. The method of producing catalytic cores for useintubularreaction chambers which consists in producing a substantially plastic mixture composed of iron oxide, a carbonaceous and a cementitious material, molding said mixture while in said plastic state in the form of an elongated rod or core, and then subjecting said mixture to temperatures sufiiciently high to'efiect the burmng' of said carbonaceous material and thehardening or of the mixture into its desired rmanent like form, the burning of sai carbonaceous material servin to render the finished rod or 6 core gubetanti porous, whereby a large surface area of e ferrous oxide is exposed for reaction facilitatin purposes. t In testimony whom; we aflix our signaures.

1o AUDLEY E. HARNSBERGEB.

CLYDE L. SMITH. 

